1. Field Of Invention
The invention relates to an apparatus and to a method for treating the internal surfaces of walls of a tank, in particular for spraying an insulating material, for example a polyurethane foam, onto the tank walls, where the tank has at least two flat wall parts interconnected by a curved wall part.
2. Description Of Prior Art
Examples of tanks requiring treatment are the tanks of seagoing tankers for the transport of liquefied natural gas or liquefied methane. These tanks are basically prismatic, with the intersecting walls having been rounded off at the intersections, so that in such tanks adjacent flat wall parts are interconnected by a curved wall part.
When treating the internal surfaces of such tanks one of the problems is to control displacement of the treating tool along both the flat wall parts and the curved wall parts. Unless this is done, all wall parts are not treated in a similar manner and the quality of the treatment is not the same for all the various wall parts.